Internal-combustion engine.



C. E. DURYEA.

INTERNAL GOMBUSTION ENGINE.

APPLIUATION FILED Amma, 1910.

1,107,501 Patented Aug. 18, 1914.

2 SHEETS-SHEET 1.

THE MORRIS PETERS CO., PHOToLlTHo.. WASHING roN, D, C.

C. B. DURYEA.

INTERNAL GOMBUSTION ENGINE.

APTLIUATION FILED APR.28, 1910.

1,107,501. Patented Aug.18,1914.

2 SHEETS-SHEET 2.

THE Nnnnm PFM-Ps co., PHoTo-LlTHo, WASHINGTON, D. C, I

CHARLES E. DURYEA, OF READING, PENNSYLVANIA.

INTERNAL-COMBUSTION ENGINE.

Specification of Letters Patent.

Patented Aug. 18, 1914:.

Application led April 28, 1910. Serial No. 558,235.

To all 'whom t may concern:

Be it known that I, CHARLES E. DURYEA, a citizen of the United States ofAmerica, and resident of Reading, in the State of Pennsylvania, haveinvented certain new and useful lmprovements in Internal-CombustionEngines, of which the following is a specification.

My invention relates to the class of internal combustion enginescommonly termed two-cycle wherein the piston uncovers an exhaust portnear the end of theworking stroke and wherein the next charge is, by thesame motion of the piston, lightly compressed in the crank box and bythis com pression is transferred to the cylinder ready for compressionby the piston on its return stroke.

The objects of my invention are the overcoming of some of the defects ofthe usual type of two-cycle engine as well as the attainment of speedsusually considered beyond the practical range of this class of engines.Among these objects may be mentioned means for insuring more completeintroduction of explosive mixture or air into the crank box, more directtransfer (and with greater completeness) of the charge to the firingchamber, better cooling of the piston head and cylinder head, lessadmixture of thenew charge with the old during the expulsion of the oldand admission of the new, positive ignition of the new charge at theright time and place, simplification of the ignition system and of theconstruction of the engine, particularly with regard to the heatedcondition under which a high speed engine, especially if air cooled,must work, and a number of other objects which will appear in thespecifications herewith. I accomplish these objects by the mechanismshown in the accompanying drawings in which- Figure l is a sectionalelevation of the parts embodying my present improvements and such otherparts as are necessary to a proper understanding thereof. Fig. 2 is anend view looking at the interior of the piston. Fig. 3 is an endelevation of the opposite end of the piston removed. Fig. l is anenlarged cross section on the line 4-4 of Fig. 1. Fig. 5 is aperspective view of the mounting and housing for the spring.

Similar letters refer to similar parts.

The explosive charge is admitted in the usual way from any preferredform of carbureter to the crank box.

From the crank box it the mixture is passed through a valve c in thehead d of the piston. It is well known that the center of the piston isthe place most ditlicult to cool 1n most engines. By passing the freshmixture through it, this objection is overcome. Here I lit a very largevalve c and make this of spheric section so that it will take thepressure of the explosion with very little amount of metal. Further Isupport this valve c and stem well up into the spheric portion so theweight of the end of the stem and the spring attached thereto, `balancesthe weight of the head and the valve has no tendency to drop down at thehead and fail to strike its seat properly. This mounting fits it to thehorizontal type of motor without placing the valve cross wise the axisof the piston as has been done. I provide in this mounting d2 a housingfor the spring cl3. This serves several purposes. It insures that abroken valve stem does not get loose and into the crank case where itmight get under the cranks and damage the case. Also that the spring dais housed from the larger part of the volume of the charge and so is notexposed to heat if this charge should by chance take re while in thecrank box and rush out past the spring while hot and burning. Suchexposure would heat and destroy the temper of the spring.

vlln order that the fresh charge may not mix with the old chargeexcessively, I provide a nozzle Z4 to the piston and direct the chargeup toward the center of the cylinder head in a round stream of smallcircumference and cross area and consequent rapid speed. The opening ofthe nozzle Z4 is less than the diameter of the valve c so if the valveshould break from its stem or mounting d2 itl could not get out into thecylinder proper and be the cause of damage. The nozzle Z4 is alsopreferably small so that it may not expose a large area to the burningcharge when ignited and it is made a part of the piston so that the heatmay be carried by the continuous metal kdown to the walls of the pistonand there be cooled by ioo contact with the cool walls of the cylinder.The cylinder head e is made spheroidal, somewhat elongated, so as toprovide 'room for the nozzle and so as to lbest mass the stream of newcharge and retain it in the cylinder head instead of letting it passdown the walls and out the exhaust ports f f. In the more commonconstructionswherein the new charge is admitted by a port uncovered bythe piston shortly after' the exhaust ports are opened, the new chargeis turned up one side of the cylinder with the result that does not massin the head but largely by its inertia rushes" ver'tle t0n and down andout the other side with'the exhaust. rIhis is specially'true of engineshaving hemi-spheric heads yyet it is well known that the hemi-spheijicshape of head offers least wall surface to absorb heat.

In the Imore common CODS'Kruction the ports must extend well aro-und thecylinderl circumference in order to get the new charge in and the oldcharge out quickly and even under most favorable conditions',authorities on' two-cycle automobile engines assert that the exhaustports should be uncovered nearly 600 before dead center.l Suchuncovering results in waste of power and a noisy y exhaust. I, byextending the exhaust ports i all around the cylinder with such bridgesas o are necessary for' strength .and to hold the rings in place tothepiston, can run at high speed with exhaust ports which uncover but oto100 ahead of dead center, about half l the usual distance from Adeadcenter. This adds tothe power and economy ofthe en-g gine but does notmaterially lessen the time for admission due to the fact that the valvec in the piston is verylarge and so can let the transfer be made quicklyand also that it v can open just as soon as they pressure is off of itand remain open till theexhaust port is closed and the pressure on theworking side o f the valve as great as that on the crank box side.' Thismethod of admission pre'- vents any possibility,V of rush of burninggases back into the crank box and insures that the old'charge isexpanded and cooled by this expansion below the burning point beforethek new is admitted by thev opening of the valve, irrespective of theengine speed. It is also readily seen that Yin high speed engines of thevmore common WP?, the short space between the two ports offers a readypassage for gases under compression in the crank box to pass around thepiston parallel to the usual piston rings and escape into the exhaustpassage, or when there is vacuum in the crank box, for the burned gasesin the exhaust pipes to be sucked back into the crank box to a greateror less extent; In engines which are run quite vcool the oil willlargely pack this space but in automobile and aeronautic work wherecooling water is not rreadily had, the oil gets very'hot and thin and sodoes not offer much hindrance to the passage of gas in eitherdirectionas stated. This is particularly true in air cooled engines where pistonsare made considerably smaller than the cylinder bore to allow forexpansion.

I show in Fig. l the construction of piston which consists of the shellof which the nozzle cl* forms part, the head CZ and the valve mountingcl2 which also serves as a stand for the piston pin bearing g g. Thesaid bea-rings g g, the mounting cl2 and the head CZ are all held inplace by studs 72, 71, fastened to the piston proper and having nuts z'zf. on their ends tof bind the bearings and all parts Vtogether; By thisconstructiomthe pistone-pin bearings never get hot for they have verylittle connection with hot vparts and are cooled by the rushof the newcharge by them on its way to the cylinder proper. The valve action Ihave described prevents the fresh gas from being exposed tothe old tillthe pressure of the 'old haspassed away on which account there is verylittle likelihood that there*v will be backring into the crank casebutto prevent this even in case the valve spring d? should break, Iinsert a screen of woven wire c between the piston head Zand the valvemounting d?. Thisl has a very large area and so offers very littleresistance to the passage of the gases. e It is not likely tov clogeasily and if clogged can be reinoved and cleaned easily, when thepiston is out of the engine.` One of the requirements of an automobileengine is that it be flexible. n That is, it must be capable of ruimingat low speeds and under the action of atluottle as dees a steam engine.In the common two cycle engine throttling results in less admission ofmixture from the crankcase and as a result of this more of the old gasesare held in the cylinder. This dilutes the new charge veryv much andmakes the engine likelyv to miss fire through failurel to ignite thelittle new charge that was admitted. My construction causes the littlenew charge admitted to pass into and through the noz-- zle Zt washingout the old ahead of it and remaining in the nozzle quite fully.` I thenprovide a spark forignition in the nozzle and thus make sure that thefresh charge however small will ignite because it is un` diluted or notlargely diluted. Further by igniting the charge farthest from theexhaust ports 'I insure that this gas ismost fully burned when theexhaust opens Vand is therefore most sure to be not burning when thefresh charge enters, thus again 'insuring that at'high speeds the enginewill not fail to function properly or backfire.

I show in Fig. l a formv ofinake and break sparker which issuited to myuse. This consists of a plug 76 screwed or fas-r tened into vthecylinderfin any well known manner. The end of this plug 7c has a`pivoted lmovable electrode Z attached thereto and of such shape thatmo-tion of the piston against its shorter end will lift the longer endaway from the insulated electrode m. These Contact ends stand slightlyout of the center line of the plug and this permits the insulatedelectrode m to be eccentric at its end and be adjusted forwear or timeby slightly twisting it. The movable electrode Z has a push rod abearing against the outer surface of its short arm, and far out from theplug body is a spring 0 which keeps the two points in contact. Thelocation of this spring 0 keeps it from the heat far enough to insureits temper remaining intact. It is evident that if the end yof thepiston nozzle (Zt contacts with the short arm of the electrode Z it willseparate the contact points and cause an electric arc if current isflowing at the time of the separation. But it is well known that forhigh speed the spark should occur some time in advance of the need ofpower so as to give the explosive mixture time to burn. This sparkadvance is usually gotten by some manually controlled device but,especially in aeronaut-ic work, it is essential that as few controllingdevices as possible be present. I therefore fit to the nozzle Z4 a loosebar Z5 headed at each end and sliding in a guide hole provided thereforin the structure of the nozzle (Z4. The bar Z5 is longer than the guidehole and will move lengthwise the pistons so far as this excess lengthwill permit at each piston stroke if the piston is moving fast. If thepiston is moving slowly, as when turning the engine over by hand, thebar Z5 will simply move with it and will break the sparker circuit whenthe piston is almost at the proper dead center. This will be too nearthe dead center for the engine to reverse its direction or back-kick.But when the piston is moving fast, rapidly acc-elerating its motion tothe center of its stroke and as rapidly retarding to the end of thestroke the bar @Z5 will accelerate with the piston but being longer thanits guide and therefore free to move with relation to the piston willnot retard with the piston but will throw forward to the limit of itsmovement and arrive in contact with the arm of the electrode Z soonerthan if not thrown forward. It will therefore make the spark sooner andgive the advanced spark position desired. Instead of a loose bar, otherforms of the loose mass may be employed. This method of advance is not avariable method because up to certain speeds it does not advance, thenits advance will be uncertain till still higher speeds are reached whenit will be found positive in action. By some experiment the properamount of advance for best average high speeds can be found and thespark position fixed at that point. Practice seems to indicate that thisproper advance is about 1g inch of piston movement in an engine having apiston stroke of 4F25 inches. .But the quality of the mixture and thesize of the spark s-eem to have some effect on this position. The largespark does not seem to require so great an advance and the power seemsto be greater with the large spark. I therefore prefer to supply thisplug with electricity from some source of energy which is not scanty orunreliable, particularly at high speeds.

One end of the wire w may be lgrounded on the engine and the othercarried to the plug in a single cylinder engine or in the two cylinderengine most used by me, both wires go to their respective plugs. Ilubricate these engines by feeding cylinder oil with `the fuel inproportions o-f about one to two pints to each five gallons of fuel, andthis not only gets rid of the complications of oilers but feeds oilproportionate to the power and the oil keeps the leather joints fromgetting hard.

It will be seen that my design not only insures charges of like qualityand of large size but that it transfers these charges in the most directmanner to the extreme head of the cylinder cooling the piston, the sparkplug and the cylinder head and passing through the old charge with theleast presentation of surface to the old charge and forcing the oldcharge out the exhaust ports most evenly. Further my location of andsize of spark insures firing even the smallest charges and firing thatpart of the charge near the valve early so it may be burned andextinguished before the next charge enters. The spring tension on thevalve c holds it against rising except when there is suliicient pressureunder it to insure a flow of new charge faster than the usual rate offlame propagation and thus insures freedom from back firing with leanmixtures even if the screen c were absent. My oiling method insuresperfect lubrication of the various parts without complexity and loss ofpower and proportionate to the power being produced. The late openingexhaust ports give increased power and quick escape of the gases as wellas even distribution of the heat of the exhaust.

While I have given my preferred method of accomplishing the objects setforth modiiications thereof may be used without departing from thespirit of the invention.

To get the valve e in place, the mounting Z2 is usually made in twoparts. The head Z is shown of disk shape but may be coned and fitted toa coned seat for easy removal.

I have described this engine cylinder and the piston therefor asmachined inside and out but without specially calling attention to thisfeature of the design. Such method of making them insures concentricityand `that expansion under the heat of hard workL does not distort themas would likely be the case if they were not concentric and even walledaround.

I have found by experiment that if the eX-1 haust opening is notprovided on all sides the old charge goes to the open side and isfollowed by the new with resultant dead space opposite the port. I cantherefore place the nozzle of the piston eccentrically and the spar-kerlikewise and thus lessen this: dead space but the work of machining isgreater in this event and it is only warranted when it is not convenientto cut the eX-. haust port all around (excepting the neces sary bridgesfor strength, of course). I have; shown the piston pin as supported inbear-- ings held by the studs but it will be evident` that the morecommon construction wherein the pin is fixed to the studs and thebearings are in the rod end, will serve just as well. I' do not attachthe pin to the walls of the piston becaus-e when the piston expands`-under heat the pin does not and this dis. tort-s the piston. The shapeof the nozzle has much to do with the results attained, The outersurface makes an easy line for the flow of the exhaust gases andpresents no corners to get overhot. The base has much metal in it andlarge connecting area with the walls of the piston so it draws the heataway from 1 the point rapidly. The point is convergent so as to throwthe new charge into a small` round rapidly moving stream and to becooled by it. It made divergent the point does not properly cool.

I claim- I. In a high speed gas engine, a pistonf having a head and anintegral nozzle above? said head and a valve mounting within the, pistonand' removable from beneath the head, s said valve mounting beingindependent ofi the nozzle; u 1

2. In a high speed gas engine, a piston: having an integral nozzle, ahead, and a` valve mounting and valve beneath the head, -g

said mounting being independent of the nozzle and mounted within thehead and remov- 4. In a high speed gas engine, a piston having anintegral nozzle above its head, the head being of greater diameter thanthe nozzle outlet, a valve mounting, a valve and means detachablysupporting said valve and valve mounting beneath the head and permittinwof removal thereof in a direction away :trom the nozzle.

5. In a high speed gas engine, a piston embodying a shell, a nozzlerigid with the shell, a head detachable from the shell and a valve andvalve mounting removable from the shell in a direction away from thenozzle,

said valve being located beneath the head and removable by movement in adirection away from the nozzle.

6. In a high speed gas engine, a piston embodying a shell and a nozzleintegral therewith, a` detachable head within the shell, meansd'etachably connecting said head and shell, piston-pin bearingssupported upon said means, and a valve mounting also supported by saidmeans.

7. In a high speed gas engine, a piston shellhaving integral nozzle,studs mounted in said nozzle, a piston head, a valve mounting, a valvewithin the nozzle of greater diameter than the nozzle outlet andpistonpin bearings supported by said studs, with means for detachablyuniting said bearings, mounting and head.

' Signed by me at Reading, Penna., this 15th day of April 1910. CHARLESE. DURYEA. IvVitnesses:

Riina E. DURYEA, D. M. STEWART.

Copies of this patent may be obtained` for ve cents each, by addressingthe i Commissioner of Patents, i Washington, I). G.

